1. Field of the Invention
The invention relates to a wireless illumination controller and, in particular, to a wireless illumination controller with the function to set the lowest driving power for a user to tune to the lowest brightness of a light bulb. It can be flexibly applied to light bulbs of different brands without flickering.
2. Description of Related Art
People nowadays value life quality more. Home control systems have become more popular. One of the most commonly seen home control systems is the illumination controller. It is electrically connected with light bulbs at home for its user to adjust the brightness thereof. The user can thus increase the brightness of a light bulb during work or reading, whereas decrease the brightness of a light bulb before or during sleep.
The illumination controller is connected in series between the light bulbs and the AC power source. Whether adopting a variable resistor or a power gate element, it always comes with a knob for the user to adjust the brightness of light bulbs. The angular position of the knob is used to determine a corresponding resistance or the voltage phase of the AC power source, thereby adjusting the current or power of the circuit and thus the brightness desired by the user. There are many different light bulbs on the market. Energy-saving and LED light bulbs have gradually replaced conventional halogen light bulbs. Such light bulbs are equipped with a driving circuit. Therefore, a special illumination controller is required in order to properly adjust the brightness thereof. However, this is apparently inconvenient for users. When the special illumination controller is used on light bulbs of different brands or of same brand but of different powers, the problem of flickering may occur.
With reference to FIG. 8, the reason for the flickering is that light bulb A and light bulb B of different brands or different powers have different characteristic curves C1, C2. The driving powers PL1 PL2 for the respective lowest brightness (hereinafter referred to as the lowest driving power) are not consistent. Therefore, once the lowest driving power that can be output from a special illumination controller is lower than that of the current light bulb, the light bulb is likely to flicker when the user tunes the special illumination controller to its lowest driving power.
For example, suppose the user uses the illumination controller for light bulb B to adjust the brightness of light bulb A. Since the lowest driving power of C2 is lower than that of C1, there is no sufficient power to drive light bulb A when the user tunes the special illumination controller to the lowest power. Light bulb A thus flickers. In this case, the user has to tune up the special illumination controller in order to prevent the flickering. However, the user may think that either the special illumination controller or the light bulb is out of order and wants to replace it.
Suppose the user uses the illumination controller for light bulb A to adjust the brightness of light bulb B. Since the lowest driving power of C1 is higher than that of C2, the user cannot tune the special illumination controller for light bulb A to obtain the lowest brightness of light bulb B. The adjustable brightness range is thus limited. In summary, the above-mentioned drawbacks and problems occur if light bulbs are not associated with the corresponding illumination controller.